I am getting ready to replace the lower corner skins on my 71 globetroter. I was only planning on removing the interior needed to replace these skins but got re-educated on interior panel removel and I am now removing all of the interior skins in order to get the interior crown ends off. I found this corrosion on the aft lower skin. It was caused by a piece of galvinized steel that was used for the storage compartment in the rear bumper. I will be replacing this skin now and replacing the galvinized with aluminum. I also will be replacing all of the stringers that run for and aft between the frames and adding several more. To be honest, I am less then impressed with the quaility of construction on this Airstream. Alot of the stringers have the rivets completly missing the mating flange or no Edge Distance at all, or holes in the radius of the vertical flange. The stringers also do not tie into the frames, and they appear to be cut off of the raw stock with either a hand axe or a meat cleaver. I was very dissapointed that I found this poor craftsmanship on a supposedly high end couch. I will post pictures of what I,m seeing after I get the rest of the interior removed

one thing for sure, AS did not use any of us airplane guys to build their stuff!I looked at the new models with the alu interior. what a crying shame the fit of the panels is 3rd grade. At least you won't be leaving the dirt with your AS. You fly wood aircraft? I'm restoring a Loehle P-5151. Tim

If I get a minute, I'd like to drive up from Palmer Lake and take a look. I've partially removed my interior skins on the Overlander and found the rivets pretty much in the ribs. Only big problem is one rivet was directly over some wiring, so as I drilled it out a few sparks flew, which really put the beak on me.

one thing for sure, AS did not use any of us airplane guys to build their stuff!I looked at the new models with the alu interior. what a crying shame the fit of the panels is 3rd grade. At least you won't be leaving the dirt with your AS. You fly wood aircraft? I'm restoring a Loehle P-5151. Tim

The Wood reference of Aerowood means that Woodworking is a hobby of mine and I use this name in other forums. I,m An A&P and a Flight Eng. on a C-130. We also operate a Gulfstream V. I did build a Pitts S2B many years ago and have been involved with other Kit Aircraft as well. The Globetrotter is my current project as I have to change 6 skins now, along with the stringer problems. I,m going to try to bend all the new stringers up today. We have a CNC press brake and it will take longer to set it up then to run the parts. I,m going to make a bunch, so if anyone needs some, I will have them. I,m making 2 styles. Zee's and C channels, 1inch legs and total height of 1.750, .040 thick, 2024-T-3.

If I get a minute, I'd like to drive up from Palmer Lake and take a look. I've partially removed my interior skins on the Overlander and found the rivets pretty much in the ribs. Only big problem is one rivet was directly over some wiring, so as I drilled it out a few sparks flew, which really put the beak on me.

Zep

Sure any time just let me know when, I,m in and out alot. The trailer is over at my dad's house in Golden.

Hi Aerowood; Please allow me to add my two cents into your dillema. The one important issue in an AS which no one makes a mention of, is a proper polarity of your 110V wiring, along with grounding being eaqually important. First, you should determine reason for the corrosion, before you attempt to replace the affected area of skin. Unless you eliminate the cause of your problem, your repair will only hide the problem temporarily. First make a visit to your electrical supply house and arm yourself with a polarity tester. Cheap, plug in, indicator with three lights. Following are the reasons for doing so; Reverse polarity may mean dumping 110 Volts thru your chassis of your AS. Remember, current always takes the easiest path of ressistance. Best connection is directly thru a copper wire [unless you can afford silver or gold wire]. In case of reverse polarity or weak grounding, current will seek a next best path to return to it's source. If this happens to be your chassis, you loose. If the current is forced to travel thru chassis and not find good clean connection, it will try to bridge next best connection by removing the less noble metal and deposit it on more noble material in attempt to repair that connection. This is called electrolisys. You may not necessarily feel the shock because the current may be very low and the tires isolate the AS from completing path to ground. Partial shorts caused by presence of moisture [which is conductive] will also send current into chassis. Send some current thru two dissimilar metals touching each other, and you got a accelerated corrosion process with the help of electrolisys. You should as well, test your wiring for possible shorts to chassis. [If you are willing to do it, I will provide you with info how to]. Bare exposed wires [not always visable] may send current into chassis in a presence of moisture, which can be very damaging over period of time. Especially in the aera of weak connection or dissimilar metals the stray currents can have a very adverse effect. What about the possibilty of revesed polarity of power supply at the campground? Do you think that it is impossible? You would be surprised. This is exactly why majority of marina's will not allow you to plug in your boat to their supply line, with a homemade cord which may have altered polarity. Water and moisture are very conductive to current, this is why some are not alive to tell the story.
While your problem may be strictly related to dissimilar metals or road salt, it is good to be sure what the cause is. I am sorry for throwing in another monkey wrench into your problem but, unles you do it right the first time the job is not done. Thanks, "Boatdoc"
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Some men do not hessitate to repair the damage, others sit down with coffee and wonder why it happened first.

Hi Aerowood; Please allow me to add my two cents into your dillema. The one important issue in an AS which no one makes a mention of, is a proper polarity of your 110V wiring, along with grounding being eaqually important. First, you should determine reason for the corrosion, before you attempt to replace the affected area of skin. Unless you eliminate the cause of your problem, your repair will only hide the problem temporarily. First make a visit to your electrical supply house and arm yourself with a polarity tester. Cheap, plug in, indicator with three lights. Following are the reasons for doing so; Reverse polarity may mean dumping 110 Volts thru your chassis of your AS. Remember, current always takes the easiest path of ressistance. Best connection is directly thru a copper wire [unless you can afford silver or gold wire]. In case of reverse polarity or weak grounding, current will seek a next best path to return to it's source. If this happens to be your chassis, you loose. If the current is forced to travel thru chassis and not find good clean connection, it will try to bridge next best connection by removing the less noble metal and deposit it on more noble material in attempt to repair that connection. This is called electrolisys. You may not necessarily feel the shock because the current may be very low and the tires isolate the AS from completing path to ground. Partial shorts caused by presence of moisture [which is conductive] will also send current into chassis. Send some current thru two dissimilar metals touching each other, and you got a accelerated corrosion process with the help of electrolisys. You should as well, test your wiring for possible shorts to chassis. [If you are willing to do it, I will provide you with info how to]. Bare exposed wires [not always visable] may send current into chassis in a presence of moisture, which can be very damaging over period of time. Especially in the aera of weak connection or dissimilar metals the stray currents can have a very adverse effect. What about the possibilty of revesed polarity of power supply at the campground? Do you think that it is impossible? You would be surprised. This is exactly why majority of marina's will not allow you to plug in your boat to their supply line, with a homemade cord which may have altered polarity. Water and moisture are very conductive to current, this is why some are not alive to tell the story.
While your problem may be strictly related to dissimilar metals or road salt, it is good to be sure what the cause is. I am sorry for throwing in another monkey wrench into your problem but, unles you do it right the first time the job is not done. Thanks, "Boatdoc"
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Some men do not hessitate to repair the damage, others sit down with coffee and wonder why it happened first.

I don't think that it was a polarity problem, but if it was it's gone know, because I completly removed all the wiring to do a complete rewire. Yes I do know what I,m doing. I completly wired the weather research bus on our C130. We can supply scientists with 100 amps of 115vac 60 hz single phase, 200 amps of 28vdc. I took the power from the number 4 engine which supplies 60 KVA 115vac 400hz 3 phase. I use phase A to power the 8 frequecy converters, Phase B I run thru 2 100amp transformer rectifiers for the 28vdc and phase C is used for 28vac and 12vdc.

I finally got the interior completly removed. I will start replacing the stringers and tieing them into all the frames this weekend, before I tackle the new skins. I will also replace the foorboards as skins come off.

Hey Aerowood; It sure looks as you are well on the way. Looks great in pic's. That same job is awaiting me, as soon as the boat winterizing season is done with. At the same time, I must wait for arrival of my new Dexter axles. New SS frame is waiting for them as well. My shell is gutted inside except inside skins and floor. First, I intend to make new banana wraps and belly pan. The belly pan edges will be bent over to form a hook to which opposite bend hook on banana wrap will interlock with. Large head 8-32 SS screws will attach the belly pan, no rivets. The wraps will be sealed at final assembly with 3M 4200 under the upper banana skin trim. Inside wiring and plumbing will be next. After that, the shell with the old floor will be placed on the new trailer and brought inside the shop. Next we will strip inside skins and brace the ribs. With roof vents removed, shell will be lifted by inserted pipe with the help of two hoists. New aluminum skinned 5/8 plywood will be used, which at final assembly of the floor will be insulated from frame with 3M 2228 Mastic Tape. Joints between the floor section will be sealed by the same at final installation with applied pressure by using long carpenters clamps. Once the floor is pre fitted and all the plumbing and electrical opening are in a proper place up and sealed, the belly pan will come down. Tracing of frame outlines on the floor sections will help in pre cutting Prodex and gluing them over 1/2' rigid urethane foam strips every 16" to create air barrier between floor and insulation. I will allow extra 2" on all sides to glue Prodex to frame at final assembly. With all connections from inside the belly pan up and above the floor shell will be attached to the frame. From here I should be on a easy street. Let me know what you think I should look out for. Thanks, "Boatdoc"

Sounds pretty good. I like the Idea of air space between the bottom of the floor and the insulation. I,m not familiar with the type of 3M sealent you are using but I'm sure you,ve checked it out. I,m using an aircraft sealent called PRC (or Pro Seal) that is used to seal fuel tanks. I've been saving the stuff that the shelf life has expired. The PN is PR1432 B20. I am also going to install plywood splines on the floorboard jionts. It was such a nice weekend last Sun. that I removed the bananna wrap and belly skin, instead of working on the stringers. I'm replacing all the belly skin and reforming the bananna on a small English Wheel that I got my hands on. It appears that the bananna wrap is made of annealed or some other dead soft aluminum. I will be installing nutplates on the frame for reattach of belly skins. ALL new aluminum will be etched, alodined, an Epoxy primed. I'll be using a primer that is also used in the marine industry. I,ve got alot of work to do and it's starting to get cold. We are supposed to get snow tonight. I,m also working outside, My boss won't let me take it into the Hanger. I think this is very narrow minded of him.

Hey Aerowood; Boy, your boss sure does not understand your needs. Just a joke. The sealer I have is in a form of a tape 2" wide and 0.65" thick and it is packed in 10' rolls. It is a rubber mastic tape relatively dense an boy does it stick. What I like about it that the shrinkage is very nominal over long periods of time. The corners of banana wrap are available from airstream so I will purchase them, and the straight runs I will form myself. They will be acid etched and neutralized with Alondine. I have a couple of gallons of BRINER paint which was used to paint steam valves. It is a high temp paint of cold set silicone base- heat cured finish. I cannot find any info on it bur the stuff is aw some. We have painted interiors in aluminum boats used in salt water. After 3 years it remains untouched by salt. The airspace between Prodex and the floor improves R value. With the Styrofoam strips glued to the floor where there is no friction or flex involved should hold the Prodex indefinitely. I will do the same thing in the walls of the shell to provide air barrier on both sides of the Prodex. Point your boss to an empty corner in your hangar, and who knows? Thanks, "Boatdoc"

I need to replace my axle also, but have decided to wait until after everything is done, weight it, and then make my choice, based on the finished weight. I will be adding a Gray water tank, and be doing a comlpete interior remodel. My wife has not yet told me how I want to do the interior yet, but it looks like some major changes are in the works, she will let me know what I want to do. I think see is trying to figure out how to put a 10 pound ham in a 5 pound can. I've got to rein her back every now and then.